Dental glass

Abstract

The present invention relates to a dental glass containing 50 to 70 wt. % of SiO 2 , 5 to 18 wt. % of Al 2 O 3 , 6.1 to 30 wt. % of MgO, 1 to 15 wt. % of La 2 O 3 , 1 to 15 wt. % of WO 3 , 0.1 to 8 wt. % of ZrO 2 , and optionally further oxides except for the oxides of Sr, Ba or alkali metals, wherein the stated quantities in total add up to 100 wt. %.

1. A dental glass containing 50 to 70 wt. % of SiO 2 ,
 5 to 18 wt. % of Al 2 O 3 , 
 6.1 to 30 wt. % of MgO, 
 1 to 15 wt. % of La 2 O 3 , 
 1 to 15 wt. % of WO 3 , 
 0.1 to 8 wt. % of ZrO 2 , 
 and optionally further oxides except for the oxides of Sr, Ba or alkali metals, wherein the stated quantities in total add up to 100 wt. %. 
 
     
     
       2. The dental glass as claimed in  claim 1 , wherein the sum of La 2 O 3 +WO 3  is 8 to 20 wt. %. 
     
     
       3. The dental glass as claimed in  claim 1 , wherein the sum of Al 2 O 3 +La 2 O 3 +WO 3  is 16 to 38 wt. %. 
     
     
       4. The dental glass as claimed in  claim 1 , wherein it contains
 50 to 70 wt. % of SiO 2 , 
 9 to 15 wt. % of Al 2 O 3 , 
 6.1 to 30 wt. % of MgO, 
 1 to 18 wt. % of La 2 O 3 +Y 2 O 3 , 
 1 to 12 wt. % of WO 3 , and 
 0.1 to 8 wt. % of ZrO 2 , 
 wherein the sum of all components adds up to 100 wt. %. 
 
     
     
       5. The dental glass as claimed in  claim 4 , wherein the sum of La 2 O 3 +Al 2 O 3 +Y 2 O 3 +ZrO 2  is 16 to 38 wt. %. 
     
     
       6. The dental glass as claimed in  claim 1 , wherein it contains 8 to 20 wt. % of MgO. 
     
     
       7. The dental glass as claimed in  claim 1 , wherein it contains 0 to 15 wt. % of oxides of other divalent metals, except for Sr and Ba. 
     
     
       8. The dental glass as claimed in  claim 7 , wherein it contains CaO and ZnO. 
     
     
       9. The dental glass as claimed in  claim 1 , wherein it contains 0 to 20 wt. % of oxides of other trivalent and/or tetravalent metals. 
     
     
       10. The dental glass as claimed in  claim 9 , wherein it contains B 2 O 3  and/or TiO 2 . 
     
     
       11. The dental glass as claimed in  claim 1 , wherein it contains 0 to 4 wt. % of Ag 2 O. 
     
     
       12. The dental glass as claimed in  claim 1 , wherein it contains from 0 to 2 wt. % of halides and/or sulfates. 
     
     
       13. A method for the production of dental glasses, wherein
 a) a glass melt is produced in the composition as claimed in  claim 1 , 
 b) a glass frit is produced by cooling of the melt, 
 c) the glass frit is pre-pulverized and 
 d) a fine milling to powder is performed. 
 
     
     
       14. The method as claimed in  claim 13 , wherein the glass frit is produced by freezing of the melt. 
     
     
       15. The method as claimed in  claim 13 , wherein the pre-pulverization of the glass frit is effected to a size of 5 to 30 μm. 
     
     
       16. The method as claimed in  claim 13 , wherein the fine milling is effected by means of a wet milling. 
     
     
       17. The method as claimed in  claim 16 , wherein the fine milling is effected in a suspension with a solids content of 5 to 50 wt. %. 
     
     
       18. The method as claimed in  claim 16 , wherein the fine milling is effected to a particle size of 20 to 50 nm. 
     
     
       19. A dental composite comprising the dental glass as claimed in  claim 1  as a glass filler.